Pugio grips - why so thin?

[Tarbicus]

A thin grip is useful for a weapon used to stab with I guess, considering the thinness of an epee's grip; held out with the hand at an angle to the wrist and forearm, the space within the hand is more restricted forming a tighter diameter for the little finger to still be able to keep contact with the palm and therefore maintain a hold. The bulge in the middle of the pugio grip would mean that where the fingers form a larger diameter a hold on the pugio handle is still maintained.